Multi-channel distillation column packing

ABSTRACT

Described herein is a column packing for a distillation apparatus, the column packing having an upper end opposite a lower end, the column packing comprising: a body extending along a central axis, the body comprising: a central channel extending parallel to the central axis, the central channel comprising a first open end opposite a second open end; and a plurality of perimeter channels circumscribing the central channel, each of the perimeter channels comprising a first open end opposite a second open end wherein the multi-channel body is formed of fluoropolymer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. Non-Provisionalapplication Ser. No. 16/367,366, filed Mar. 28, 2019, which claims thebenefit of U.S. Provisional Application No. 62/649,393, filed Mar. 28,2018. The disclosure of the above application is incorporated herein byreference.

BACKGROUND

Distillation apparatus and techniques may utilize a column in which masstransfer or heat exchange between liquid and vapor streams occurs and,more particularly, to packing elements used in such columns tofacilitate contact between the liquid and vapor streams, Many types ofmetallic or glass packings have been developed for use in mass transferor heat exchange columns. In general, these packings facilitate contactbetween the liquid and vapor streams by causing more uniformdistribution of liquid and vapor over the surface of the packing.Limitations, however, exist with the amount of surface area thesepacking elements may provide due to the cost of material and/ordifficulty in fabricating parts. Thus, a need exists for a betterdistillation packing element.

BRIEF SUMMARY

The present invention is directed to a column packing for a distillationapparatus, the column packing comprising: a first open end opposite asecond open end: a central channel; a plurality of perimeter channels;and a body extending along a central axis between an upper end oppositea lower end, the body formed of polymeric material and comprising: anouter wall extending substantially parallel to the central axis betweenthe first and second open ends of the body; an inner wall circumscribedby the outer wall and extending substantially parallel to the centralaxis between the first and second open ends of the body; and a pluralityof rib elements connecting the inner wall to the outer wall; wherein thecentral axis intersects both the first and second open ends, the centralchannel extending parallel to the central axis and the central channelcircumscribed by the inner wall; and the plurality of perimeter channelsextending parallel to the central axis, each of the plurality ofperimeter channels defined by at least a portion of the inner wall, atleast a portion of the outer wall, and at least two the plurality of ribelements.

Other embodiments of the present invention include a column packing fora distillation apparatus, the column packing having an upper endopposite a lower end, the column packing comprising: a body extendingalong a central axis, the body comprising: a central channel extendingparallel to the central axis, the central channel comprising a firstopen end opposite a second open end; and a plurality of perimeterchannels circumscribing the central channel, each of the perimeterchannels comprising a first open end opposite a second open end whereinthe multi-channel body is formed of fluoropolymer.

Other embodiments of the present invention include a distillation columncomprising: at least one of the column packings previously discussed.

Other embodiments of the present invention include a method ofdistilling comprising: distilling a substance through the one of thepreviously discussed distillation column.

Other embodiments of the present invention include a method of forming acolumn packing for a distillation apparatus, the method comprising: a)extruding a composition comprising fluoropolymer through a die to form atube having a central channel circumscribed by a plurality of perimeterchannels; b) cutting the tube in a direction perpendicular to thecentral axis to form a body comprising the central channel and theplurality of perimeter channels.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood that the detailed description and specific examples, whileindicating the preferred embodiment of the invention, are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a top perspective view of a multi-channel distillation columnaccording to the present invention;

FIG. 2 is a bottom perspective view of the multi-channel distillationcolumn of FIG. 1;

FIG. 3 is a side view of the multi-channel distillation column of FIG.1;

FIG. 4A is a top view of the multi-channel distillation column of FIG.1;

FIG. 4B is a top view of the multi-channel distillation column of FIG.1;

FIG. 5 is a cross-sectional view of the multi-channel distillationcolumn along line V-V of FIG. 4;

FIG. 6 is a cross-sectional view of the multi-channel distillationcolumn along line X-X of FIG. 4;

FIG. 7 is a schematic representation of a distillation apparatuscomprising the multi-channel distillation column of the presentinvention;

FIG. 8 is a close-up view of the distillation apparatus of FIG. 7 inregion XX;

FIG. 9 is a top perspective view of a multi-channel distillation columnaccording to another embodiment of the present invention;

FIG. 10 is a top view of the multi-channel distillation column of FIG.9;

FIG. 11 is a top perspective view of a multi-channel distillation columnaccording to another embodiment of the present invention; and

FIG. 12 is a top view of the multi-channel distillation column of FIG.11.

DETAILED DESCRIPTION

The following description of the preferred embodiment(s) is merelyexemplary in nature and is in no way intended to limit the invention,its application, or uses.

As used throughout, ranges are used as shorthand for describing each andevery value that is within the range. Any value within the range can beselected as the terminus of the range. In addition, all references citedherein are hereby incorporated by referenced in their entireties. In theevent of a conflict in a definition in the present disclosure and thatof a cited reference, the present disclosure controls.

Unless otherwise specified, all percentages and amounts expressed hereinand elsewhere in the specification should be understood to refer topercentages by weight. The amounts given are based on the active weightof the material.

The description of illustrative embodiments according to principles ofthe present invention is intended to be read in connection with theaccompanying drawings, which are to be considered part of the entirewritten description. In the description of embodiments of the inventiondisclosed herein, any reference to direction or orientation is merelyintended for convenience of description and is not intended in any wayto limit the scope of the present invention. Relative terms such as“lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,”“down,” “top,” and “bottom” as well as derivatives thereof (e.g.,“horizontally,” “downwardly,” “upwardly,” etc.) should be construed torefer to the orientation as then described or as shown in the drawingunder discussion. These relative terms are for convenience ofdescription only and do not require that the apparatus be constructed oroperated in a particular orientation unless explicitly indicated assuch.

Terms such as “attached,” “affixed,” “connected,” “coupled,”“interconnected,” and similar refer to a relationship wherein structuresare secured or attached to one another either directly or indirectlythrough intervening structures, as well as both movable or rigidattachments or relationships, unless expressly described otherwise.Moreover, the features and benefits of the invention are illustrated byreference to the exemplified embodiments. Accordingly, the inventionexpressly should not be limited to such exemplary embodimentsillustrating some possible non-limiting combination of features that mayexist alone or in other combinations of features; the scope of theinvention being defined by the claims appended hereto.

Unless otherwise specified, all percentages and amounts expressed hereinand elsewhere in the specification should be understood to refer topercentages by weight. The amounts given are based on the active weightof the material. According to the present application, the term “about”means+/−5% of the reference value. According to the present application,the term “substantially free” less than about 0.1 wt. % based on thetotal of the referenced value.

Referring now to FIGS. 1, 2, 7, and 8—the present invention is directedto a distillation apparatus 1 comprising at least one column packing100. The distillation apparatus 1 may comprise a distillation chamber 10(also referred to as a “distillation column”) having an inlet 11 and anoutlet 12. The distillation apparatus 1 may further comprise one or moresupports 20 that are located inside of the distillation chamber 10. Thesupports 20 may be a perforated layer. The distillation apparatus 1 mayfurther comprise one or more of the column packings 100—preferably aplurality of the column packings 100. For the distillation apparatus 1comprising a multiple supports 20, a plurality of the column packings100 may be located on the multiple supports 20 inside of thedistillation chamber 10.

The inlet 11 of the distillation chamber 10 may be fluidly coupled to afirst reservoir and the outlet 12 of the distillation chamber 10 may befluidly coupled to a second reservoir. The first reservoir may contain acomposition that is delivered to the distillation chamber 10 via theinlet 11, whereby the composition is subjected to distillation—asdiscussed in further detail herein. After distillation, the distilledcomposition may exit the distillation chamber 10 and be delivered to thesecond reservoir via the outlet 12.

Referring now to FIGS. 1-3, the column packing 100 of the presentinvention may comprise an uppermost surface 101 opposite a lowermostsurface 102 and an exposed side surface 103 extending there-between.

The column packing 100 may comprise a body 110 extending along a centralaxis A-A. The body 110 may comprise an upper surface 115 opposite alower surface 116 as well as a side surface 117 that extends between theupper surface 115 and the lower surface 116. The body 110 may becylindrical in shape.

According to some embodiments of the present invention, the body 110 maycomprise an outer wall 200, an inner wall 300, and one or more ribelements 300. During distillation, the combination of the outer wall200, the inner wall 300, and one or more rib elements 300 may provide acontact surface area for the liquid and vapor phases to mix and reachthermal equilibrium during distillation—which results in efficientfractional distillation.

Having the available surface area within the column packing 100 being afunction of the layout for the outer wall 200, the inner wall 300,and/or the rib elements 600 offers a dynamic ability to not onlyincrease the amount of available surface area but also custom tailor acolumn packing 100 to suit unique distillation needs by modifying theoverall shape of the body 110.

The body 110 may have a body height H_(B) as measured by the distancebetween upper surface 115 and the lower surface 116. The body heightH_(B) may range from about 1 mm to about 80 mm—including all thicknessand sub-ranges there-between. In a preferred embodiment, the body heightH_(B) may range from about 4 mm to about 6 mm—including all thicknessand sub-ranges there-between.

The body 110 may have a body diameter D_(B) as measured by the distancebetween opposing side surfaces 117 across the central axis A-A. The bodydiameter D_(B) may range from about 1 mm to about 20 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 2 mm to about 18 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 3 mm to about 16 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 4 mm to about 14 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 4 mm to about 12 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 5 mm to about 10 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 5 mm to about 8 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may range from about 4 mm to about 6 mm—including allthickness and sub-ranges there-between. In some embodiments, the bodydiameter D_(B) may be about 5 mm.

A ratio of the body diameter D_(B) to the body height H_(B) may rangefrom about 0.25:1 to about 4:1—including all ratios and sub-rangesthere-between. In some embodiments, the ratio of the body diameter D_(B)to the body height H_(B) may range from about 0.33:1 to about3:1—including all ratios and sub-ranges there-between. In someembodiments, the ratio of the body diameter D_(B) to the body heightH_(B) may range from about 0.5:1 to about 2:1—including all ratios andsub-ranges there-between. In some embodiments, the ratio of the bodydiameter D_(B) to the body height H_(B) may range from about 0.75:1 toabout 1.25:1—including all ratios and sub-ranges there-between. In apreferred embodiment, the ratio of the body diameter D_(B) to the bodyheight H_(B) may be about 1:1.

According to the present invention, having the ratio of the bodydiameter D_(B) to the body height H_(B) may range from about 0.75:1 toabout 1.25:1 may produce a more uniform shape of the body 110. The moreuniform shape of the body 110 may promote a randomly orienteddistribution as the column packing 100 if it is poured or “dumped” intothe distillation column 10. Random column packing orientation exposesthe maximum amount of surface area and permits the highest vaporthroughput rate, while simultaneously minimizing unwanted effects withina functioning distillation column such as “flooding” or “channeling”.

The random column packing may result in a stack of a plurality of columnpackings that extend to a stacking height. The stacking height may beequal to at least about 1.1 times the body height H_(B). In someembodiments, the stacking height may be equal to at least about 1.5×times the body height H_(B). The stacking height may be equal to atleast about 1.5× times the body height H_(B). The stacking height may beequal to at least about 2× times the body height H_(B).

Column packing 100 having a body 110 having a ratio of the body diameterD_(B) to the body height H_(B) that is less than 0.2:1 may result inlong length column packings 10 that tend to fall into a mostlyhorizontal, closely packed pattern that can impede the flow of liquidand vapor phases within the distillation column 10, leading to aflooding condition when the downward return flow of the liquid phase isslowed or blocked. Flooding greatly diminishes the efficiency and vaporthroughput rate of a distillation process.

Column packing 100 having a body 110 having a ratio of the body diameterD_(B) to the body height H_(B) that is less than 0.2:1 may result inlong length column packings 10 that can also create jams that packunevenly, causing voids having no packing within the distillationcolumn. This not only directly reduces distillation column efficiency,but contributes to the condition known as channeling, wherein thedownward return flow of the liquid phase follows a narrow path thatmixes poorly with the upward vapor phase flow, thereby destroying thenecessary equilibration between liquid and vapor phases.

The upper surface 115 of the body 110 may form the uppermost surface 101of the column packing 100. Stated otherwise, the uppermost surface 101of the column packing 100 may comprise the upper surface 115 of the body110. The lower surface 116 of the body 110 may form the lowermostsurface 102 of the column packing 100. Stated otherwise, the lowermostsurface 102 of the column packing 100 may comprise the lower surface 116of the body 110. The side surface 117 of the body 110 may form theexposed side surface 103 of the column packing 100. Stated otherwise,the exposed side surface 103 of the column packing 100 may comprise theside surface 117 of the body 110.

The body 110 may be open-ended. The body 110 may comprise a firstopen-end 111 opposite a second open-end 112. Each of the first open-end111 and the second open-end 112 may intersect the central axis A-A. Thefirst open-end 111 and the upper surface 115 of the body 110 mayoverlap. The second open-end 112 and the lower surface 116 of the body110 may overlap.

As discussed in greater detail herein, the column packing 100 maycomprise a plurality of channels 400, 500 that extend through the body110. Specifically, the column packing 100 may comprise a plurality ofchannels 400, 500 that extend between the first open-end 111 and thesecond open-end 112 of the body 110. The plurality of channels 400, 500may provide fluid communication through the body 110 between uppermostsurface 101 and the lowermost surface 102 of the column packing 100. Theplurality of channels 400, 500 may provide fluid communication throughthe body 110 such that fluid communication may exist between the firstopen-end 111 and the second open-end 112 of the body 110.

The plurality of channels of the column packing 100 may comprise acentral channel 400 and at least one perimeter channel 500. In someembodiments, the column packing 100 may comprise a central channel 400and a plurality of perimeter channels 500. The central channel 400 maybe circumscribed by the perimeter channels 500.

Referring now to FIGS. 4A, 4B, 5, and 6, the central channel 400 mayextend along a direction substantially parallel to the central axis A-A.The central channel 400 may be concentric with the central axis A-A. Thecentral channel 400 may have a uniform cross-sectional shape taken alonga direction that is perpendicular to the central axis A-A. Thecross-sectional shape of the central channel 400 may be circular. Inother embodiments, the cross-sectional shape of the central channel 400may be polygonal. Non-limiting examples of polygonal cross-sectionalshapes include quadrilateral (square, rectangle, diamond, trapezoid),pentagonal, hexagonal, heptagonal, octagonal, nonagonal, decagonal, etc.

The central channel 400 may comprise a first open-end 411 opposite asecond open-end 412. The first open-end 411 and the second open-end 412of the central channel 400 may intersect the central axis A-A. The firstopen-end 411 of the central channel 400 may overlap with the uppersurface 115 of the body 110. The second open-end 412 of the centralchannel 400 may overlap with the lower surface 116 of the body 110.

The perimeter channels 500 may extend along a direction that issubstantially parallel to the central axis A-A. The perimeter channels500 may circumscribe the central axis A-A. The perimeter channels 500can be oriented concentrically about the central axis A-A. In someembodiments, the column packing 500 may comprise two, three, four, five,six, seven, eight, nine, ten individuals perimeter channels 500.

Each of the perimeter channels 500 may have a cross-sectional shapetaken along a direction that is perpendicular to the central axis A-A.Each of the perimeter channels 500 may have the same cross-sectionalshape. In other embodiments, each of the perimeter channels 500 may havedifferent cross-sectional shapes. In some embodiments, a first pluralityof the perimeter channels 500 may have a first cross-sectional shape anda second plurality of perimeter channels 500 may have a secondcross-sectional shape—whereby the first and second cross-sectionalshapes are different.

Each of the plurality of perimeter channels 500 may be orientedsymmetrically about the central axis A-A such that each of the perimeterchannels 500 are separated from each other by an equal distance. Inother embodiments, the plurality of perimeter channels 500 may beoriented asymmetrically about the central axis A-A such that at leasttwo of the perimeter channels 500 are separated from each other bynon-equal distance.

Each of the perimeter channels 500 may comprise a first open-end 511opposite a second open-end 512. The first open-end 411 of each perimeterchannel 500 may overlap with the upper surface 115 of the body 110. Thesecond open-end 412 of each perimeter channel 500 may overlap with thelower surface 116 of the body 110.

Referring now to FIGS. 1, 2, 4A, 4B, the body 110 of the column packing100 may comprise an outer wall 200 and an inner wall 300. The outer wall200 may circumscribe the inner wall 300. As discussed in greater detailherein, the outer wall 200 may be connected to the inner wall 300 by oneor more rib elements 600 extending there-between.

The outer wall 200 may comprise an outer surface 201 opposite an innersurface 202. The inner surface 202 of the outer wall 200 may face thecentral axis A-A. The outer surface 201 of the outer wall 200 may faceaway from central axis A-A. The outer wall 200 may have an outer wallthickness tow as measured by the distance between the inner surface 201and the outer surface 202 of the outer wall 200. The outer wallthickness tow may range from about 0.1 mm to about 0.3 mm—including allthickness and sub-ranges there-between. In some embodiments, the outerwall thickness tow may range from about 0.15 mm to about 0.25mm—including all thickness and sub-ranges there-between. In someembodiments, the outer wall thickness tow may be about 0.2 mm. The outerwall thickness tow may be substantially uniform.

The outer surface 201 of the outer wall 200 may form the side surface117 of the body 110. Stated otherwise, the side surface 117 of the body110 may comprise the outer surface 201 of the outer wall 200

The outer wall 200 may have an upper edge 211 opposite a lower edge 212.The outer wall 200 may extend between the upper edge 211 and the loweredge 212 in a direction that is substantially parallel to the centralaxis A-A. The outer wall 200 may extend continuously between the upperedge 211 and the lower edge 212 such that the outer wall 200 issubstantially free of passageways extending between the inner surface202 and the outer surface 201 of the outer wall 200.

The upper edge 211 of the outer wall 200 may form at least a portion ofthe upper surface 115 of the body 110. Stated otherwise, the uppersurface of the body 110 may comprise upper surface 211 of the outer wall200 most surface 101 of the column packing 100 may comprise the uppersurface 115 of the body 110. The lower surface 116 of the body 110 mayform the lowermost surface 102 of the column packing 100. The outer wall200 may have a height as measured between the upper edge 211 and thelower edge 212 that is substantially equal to the body height H_(B) ofthe body 110. The outer wall 200 may have a diameter as measured betweenopposite outer surfaces 201 of the outer wall 200 passing through thecentral axis A-A, whereby the diameter of the outer wall 200 may besubstantially equal to the body diameter D_(B) of the body 110.

The body 110 may comprise an inner wall 300. The inner wall 300 maycomprise an outer surface 301 opposite an inner surface 302. The innersurface 302 of the inner wall 300 may face the central axis A-A. Theouter surface 301 of the inner wall 300 may face away from central axisA-A. The inner wall 300 may have an inner wall thickness t_(IW) asmeasured by the distance between the inner surface 301 and the outersurface 302 of the inner wall 300. The inner wall thickness t_(IW) mayrange from about 0.1 to about 0.3—including all thickness and sub-rangesthere-between. In some embodiments, the inner wall thickness t_(IW) mayrange from about 0.15 to about 0.25—including all thickness andsub-ranges there-between. In some embodiments, the inner wall thicknesst_(IW) may be about 0.2. The inner wall thickness t_(IW) may besubstantially uniform.

The inner wall 300 may have an upper edge 311 opposite a lower edge 312.The inner wall 300 may extend between the upper edge 311 and the loweredge 312 in a direction that is substantially parallel to the centralaxis A-A. The outer wall 300 may extend continuously between the upperedge 311 and the lower edge 312 such that the inner wall 300 issubstantially free of passageways extending between the inner surface302 and the outer surface 301 of the inner wall 300.

The upper edge 311 of the inner wall 300 may form at least a portion ofthe upper surface 115 of the body 110. Stated otherwise, the uppersurface 115 of the body 110 may comprise upper edge 311 of the innerwall 300. The lower edge 312 of the inner wall 300 may form at least aportion of the lower surface 116 of the body 110. Stated otherwise, thelower surface 116 of the body 110 may comprise the lower edge 312 of theinner wall 300.

Referring now to FIGS. 1, 2, and 4A-6, the body 110 may comprise one ormore rib elements 600. In a preferred embodiment, the body 100 comprisesa plurality of rib elements 600. Each of the rib elements 600 may extendfrom the inner wall 300 to the outer wall 200. In a preferredembodiment, each of the rib elements 600 may be integrally formed withthe inner wall 300. In a preferred embodiment, each of the rib elements600 may be integrally formed with the outer wall 200. The rib elements600 may extend from the outer surface 301 of the inner wall 300 to theinner surface 202 of the outer wall 200.

Each of the rib elements 600 may be an elongated structure that extendsin a direction parallel to the central axis A-A. The rib elements 600may comprise a first major surface 601 opposite a second major surface602. Each of the rib elements 600 may comprise an upper edge 611opposite a lower edge 612. The first and second major surfaces 601, 602of each rib element 600 may extend between the upper edge 611 and thelower edge 612 of the corresponding rib element 600.

The first major surface 601 of the rib element 600 may extend betweenthe upper and lower edges 611, 612 in a direction that is substantiallyparallel to the central axis A-A. The second major surface 602 of therib element 600 may extend between the upper and lower edges 611, 612 ina direction that is substantially parallel to the central axis A-A. Therib element 600 may extend continuously between the upper edge 611 andthe lower edge 612 such that each of the rib elements 600 aresubstantially free of passageways extending between the first and secondmajor surfaces 601, 602 of the rib element 600.

Each of the rib elements 300 may be oriented substantially radiallyabout the central axis A-A. In other embodiments, the rib elements 300may be arranged about the central axis A-A in a non-radiallyconfiguration. The plurality of the rib elements 300 may besymmetrically oriented about the central axis A-A. In other embodiments,the plurality of the rib elements 300 may be asymmetrically orientedabout the central axis A-A.

Each of the rib elements 600 may be offset from each other about thecentral axis A-A by an offset angle θ₁ that ranges from about 30° toabout 180°—including all angles and sub-ranges there-between. The offsetangle θ₁ may relate to the number of rib elements 600 that form the body110. For instance, the offset angle θ₁ may be calculated by dividing360° by the total number of rib elements 600. In a non-limiting example,the offset angle θ₁ may be about 30°, about 40°, about 45°, about 51°,about 60°, about 72°, about 90°, about 120°, or about 180°.

Each of the rib elements 600 may have a rib element thickness t_(RE) asmeasured by the distance between the first major surface 601 and thesecond major surface 602 of the rib element 600. The rib elementthickness t_(RE) may range from about 0.1 mm to about 0.3 mm—includingall thickness and sub-ranges there-between. In some embodiments, the ribelement thickness t_(RE) may range from about 0.15 mm to about 0.25mm—including all thickness and sub-ranges there-between. In someembodiments, the rib element thickness t_(RE) may be about 0.2 mm. Therib element thickness t_(RE) may be substantially uniform.

The upper edge 611 of the rib element 600 may form at least a portion ofthe upper surface 115 of the body 110. Stated otherwise, the uppersurface 115 of the body 110 may comprise upper edge 611 of the ribelement 600. The lower edge 612 of the rib element 600 may form at leasta portion of the lower surface 116 of the body 110. Stated otherwise,the lower surface 116 of the body 110 may comprise the lower edge 612 ofthe rib element 600.

The inner wall 300 may form a closed geometry about the central axisA-A. Therefore, the inner wall 300 may form a perimeter that defines thecentral channel 400. Specifically, the inner surface 302 of the innerwall 300 may form a continuous surface about the central axis A-A,thereby defining a perimeter surface that forms the boundary of thecentral channel 400. As a result, the geometry of the inner wall 300 maycontrol the cross-sectional geometry of the central channel 400.

The central channel 400 may have a length that is substantially equal tothe body height H_(B) of the body 110. The central channel 400 may havea first width (also referred to as a “first diameter”) D₁ as measuredbetween opposite inner surfaces 302 of the inner wall 300 in a directionsubstantially perpendicular to the central axis A-A. The first diameterD1 may range from about 1.6 mm to about 2.2 mm—including all thicknessand sub-ranges there-between. In some embodiments, the first diameter D1may range from about 1.7 mm to about 2.1 mm—including all thickness andsub-ranges there-between. In some embodiments, the first diameter D1 mayrange from about 1.8 mm to about 2.0 mm—including all thickness andsub-ranges there-between. In some embodiments, the first diameter D1 maybe about 1.9 mm.

In a non-limiting example, the inner wall 300 may form a polygonalshape—such as an elongated square tube shape—resulting in the centralchannel 400 having a square cross-sectional shape. In anothernon-limiting example, the inner wall 300 may form a cylindrical shape,resulting in the central channel 400 having a circular cross-sectionalshape.

The outer wall 200 may form a closed geometry about the central axisA-A. The combination of the inner wall 300, the outer wall 200, and oneor more of the rib elements 600 may define each of the perimeterchannels 500. Specifically, a portion of the inner surface 202 of theouter wall 200, a portion of the outer surface 301 of the inner wall300, a first major surface of a first rib element 600, and a secondmajor surface of a second rib element 600 may define a boundary thatdefines each of the perimeter channels 500. As a result, the geometry ofthe inner wall 300, the geometry of the outer wall 200 and/or thegeometry of each of the rib elements 600 may control the cross-sectionalgeometry of the perimeter channels 500. In a non-limiting example, theinner wall 300 may form a polygonal shape—such as an elongated squaretube shape—while the outer wall 200 forms a circular shape—resulting inthe perimeter channels 500 having a cross-sectional shape that comprisesboth linear straight edges as well as curved edges.

The perimeter channels 500 may have a length as measured along adirection substantially a parallel to the central axis A-A, wherein thelength of the perimeter channels 500 are substantially equal to the bodyheight H_(B) of the body 110.

The perimeter channels 500 may have a width as measured by a distance D2taken radially from the central axis A-A, the distance D2 being measuredbetween the outer surfaces 301 of the inner wall 300 and the innersurface 202 of the outer wall 200. The second distance D2 may range fromabout 1.0 mm to about 1.3 mm—including all thickness and sub-rangesthere-between. In some embodiments, the second distance D2 may rangefrom about 1.05 mm to about 1.25 mm—including all thickness andsub-ranges there-between. In some embodiments, the second distance D2may range from about 1.1 mm to about 1.2 mm—including all thickness andsub-ranges there-between. In some embodiments, the second distance D2may be about 1.15 mm.

The inner boundary of each of the perimeter channels 500 may span adistance D3 as measured between opposite side boundaries (i.e., betweenopposite first and second major surfaces 601, 602 of the first andsecond rib elements 600) along the outer surface 301 of the inner wall.The distance D3 of the inner boundary of the perimeter channel 500 mayrange from about 2.0 mm to about 2.6 mm—including all thickness andsub-ranges there-between. In some embodiments, the distance D3 of theinner boundary of the perimeter channel 500 may range from about 2.1 mmto about 2.5 mm—including all thickness and sub-ranges there-between. Insome embodiments, the distance D3 of the inner boundary of the perimeterchannel 500 may range from about 2.2 mm to about 2.4 mm—including allthickness and sub-ranges there-between. In some embodiments, thedistance D3 of the inner boundary of the perimeter channel 500 may beabout 2.3 mm.

In a non-limiting example, FIGS. 1-6 demonstrate a column packing 100that comprises a body 110 having a central channel 400 and a pluralityof perimeter channels 500 that include a first perimeter channel 500 a,a second perimeter channel 500 b, a third perimeter channel 500 c, and afourth perimeter channel 500 d. The four perimeter channels 500 a, 500b, 500 c, 500 d, may be arranged concentrically about the central axisA-A and all have the same cross-sectional shape.

Each of the perimeter channels 500 a, 500 b, 500 c, 500 d, may comprisean inner boundary formed by a portion of the outer surface 301 of theinner wall 300, an outer boundary formed by a portion of the innersurface 202 of the outer wall 200, and a side boundary formed by a firstmajor surface 601 of a first rib element 600 and a second major surfaceof a second rib element 600. The portion of the outer surface 301 of theinner wall 300, the portion of the inner surface 202 of the outer wall200, the first major surface 601 of the first rib element 600, and thesecond major surface of the second rib element 600 may intersect eachother to collectively form a closed perimeter defining the respectiveperimeter channels 500 a, 500 b, 500 c, 500 d.

A first perimeter channel 500 a may comprise an inner boundary formed bya first portion of the outer surface 301 a of the inner wall 300 thatintersects a first side boundary formed by a second major surface 602 ofa first rib element 600 a, which intersects an outer boundary formed bya first portion of the inner surface 202 a of the outer wall 200, whichintersects a second side boundary formed by a first major surface 601 ofa second rib element 600 b, which intersects the inner boundary formedby the first portion of the outer surface 301 a of the inner wall300—thereby collectively forming a closed perimeter that defines thefirst perimeter channel 500 a.

A second perimeter channel 500 b may comprise an inner boundary formedby a second portion of the outer surface 301 b of the inner wall 300that intersects a first side boundary formed by a second major surface602 of the second rib element 600 b, which intersects an outer boundaryformed by a second portion of the inner surface 202 b of the outer wall200, which intersects a second side boundary formed by a first majorsurface 601 of a third rib element 600 c, which intersects the innerboundary formed by the second portion of the outer surface 301 b of theinner wall 300—thereby collectively forming a closed perimeter thatdefines the second perimeter channel 500 b.

A third perimeter channel 500 c may comprise an inner boundary formed bya third portion of the outer surface 301 c of the inner wall 300 thatintersects a first side boundary formed by a second major surface 602 ofthe third rib element 600 c, which intersects an outer boundary formedby a third portion of the inner surface 202 c of the outer wall 200,which intersects a second side boundary formed by a first major surface601 of a fourth rib element 600 d, which intersects the inner boundaryformed by the third portion of the outer surface 301 c of the inner wall300—thereby collectively forming a closed perimeter that defines thethird perimeter channel 500 c.

A fourth perimeter channel 500 d may comprise an inner boundary formedby a fourth portion of the outer surface 301 d of the inner wall 300that intersects a first side boundary formed by a second major surface602 of the fourth rib element 600 d, which intersects an outer boundaryformed by a fourth portion of the inner surface 202 d of the outer wall200, which intersects a second side boundary formed by a first majorsurface 601 of a first rib element 600 a, which intersects the innerboundary formed by the fourth portion of the outer surface 301 d of theinner wall 300—thereby collectively forming a closed perimeter thatdefines the fourth perimeter channel 500 d.

According to this embodiment, each of the first, second, third, andfourth portions of the outer surfaces 301 a, 301 b, 301 c, 301 d of theinner wall 300 may be planar. Therefore, the respective inner boundariesof the first, second, third, and fourth respective perimeter channels500 a, 500 b, 500 c, 500 d may be flat (i.e., planar). According to thisembodiment, each of the first, second, third, and fourth portions of theinner surfaces 202 a, 202 b, 202 c, 202 d of the outer wall 200 may becurved—specifically, have a uniform radius of curvature as measured fromthe central axis A-A. Therefore, the respective outer boundaries of thefirst, second, third, and fourth respective perimeter channels 500 a,500 b, 500 c, 500 d may be curved and have a uniform radius of curvatureas measured from the central axis A-A. According to this embodiment,each of first and second major surfaces 601, 602, of the first, second,third, and fourth rib elements 600 a, 600 b, 600 c, 600 d may beplanar—i.e., flat. Therefore, the respective first and second sideboundaries of the first, second, third, and fourth respective perimeterchannels 500 a, 500 b, 500 c, 500 d may be planar—i.e., flat.

The body 110 of the column packing may be formed from a polymericmaterial. The body 110 may consist essentially of the polymericmaterial. In some embodiments, the body 110 may consist of the polymericmaterial.

The polymeric material may be selected from materials that exhibitchemical resistance, stability, and purity. The polymeric material maybe thermoplastic. The polymeric material may be suitable for hot-meltextrusion.

The polymeric material may be a polyolefin, polyvinyl chloride, or afluoropolymer. Non-limiting examples of polyolefin include low orhigh-density polyethylene (LDPE or HDPE) polypropylene (PP).

In a preferred embodiment, the polymeric material may be afluoropolymer. Non-limiting examples of fluoropolymer include FEP(Fluorinated Ethylene-Propylene, a copolymer of tetrafluoroethylene andhexafluoropropylene), PFA (PerFluoroAlkoxy, a copolymer oftetrafluoroethylene and a perfluoroether)—both high-purity PFA andstandard purity PFA, PVDF (Poly Vinylidene Fluoride), ETFE(Ethylene-Tetrafluoroethylene copolymer), and combinations thereof.

Fluoropolymers, including FEP and PFA, exhibit chemical resistance toalmost all but the most corrosive or reactive chemical compounds andconditions, such as intimate contact with a molten alkali metal (i.e.,lithium, sodium or potassium) chlorine trifluoride, oxygen difluorideand liquid or gaseous elemental fluorine, to name the most significantones.

With the chemical resistance, column packing 10 made from fluoropolymersoffer extreme inertness and long service life, and so are ideal forcontact with virtually all solvents and chemical compounds, even at theelevated temperatures encountered in most distillations.

In addition to extreme chemical resistance, fluoropolymers alsowithstand much higher continuous use service temperatures than the muchmore inexpensive and commonly used thermoplastic polymers notedpreviously. The following table summarizes the continuous usetemperatures of the different polymers mentioned above.

However, fluoropolymers as a class are much more difficult to extrudecompared to the usual thermoplastic polymers, because the melt viscosityof most fluoropolymers is greater, resulting in slower rates ofproduction. In addition, the extrusion processing temperatures offluoropolymers are much higher than most commercial thermoplastics,which can cause some fluoropolymer degradation as a result.

The degradation products include hydrogen fluoride and otherfluorine-containing gases which, besides being highly toxic, areextremely corrosive to the usual metals comprising extruder components(e.g., alloy steel, stainless steel) and so require the use of moreexotic metals and alloys, such as high nickel content alloys that arecapable of resisting corrosion in this hot, acidic environment.

Standard grades of FEP (and also PFA) include those containing onlyvirgin polymer, as well as grades incorporating some level ofreprocessed (recycled) material. Although standard grades of FEP and PFAmaintain a high degree of purity and function well in most laboratorydistillation applications by virtue of the inherent inertness andchemical resistance of fluoropolymers, some applications require anextreme performance level, such as those encountered in thesemiconductor fabrication or pharmaceutical manufacturing and processingindustries.

In the semiconductor fabrication industry, for example, the latestmicroelectronic chips and devices feature circuit components that arebecoming increasingly smaller in size to allow more circuit componentsto be crowded onto smaller, more compact chips.

As a result of the smaller sized circuit components, even very lowlevels of extractable impurities (such as ions, metals and particles oforganic carbon) released from standard grades of fluoropolymers canshort-circuit, corrode or otherwise alter the performance ofsemiconductor chips. These contaminants can therefore cause devicefailure if in contact with the increasingly smaller components andcircuit paths of the new microelectronic chips and devices.

Ultra-high purity (“UHP”) PFA has been developed to meet the increasingdemands of various industries for extreme purity. UHP PFA is made from100% virgin resin having the highest average molecular weight andresultant highest thermal stability and resistance to thermaldegradation over an extended time period, compared to lower averagemolecular weight grades of PFA that thermally decompose more easily.

The recommended limits and tests for extractable impurities mentionedabove are established by the Semiconductor Equipment and MaterialsInternational (SEMI) organization, in the F57-0314 standard titled“Provisional Specification for Polymer Materials and Components Used InUltrapure Water and Liquid Chemical Distribution Systems”, a part of theInternational Standards Program.

In addition to having the highest average molecular weight and thermalstability, UHP PFA, compared to standard grades of fluoropolymers,releases only the very lowest levels of Total Organic Carbon (TOC) ionicimpurities and metallic impurities. For example, UHP PFA contains only0.2% of the limit specified in SEMI F57 for surface extractable TotalOrganic Carbon (TOC) thereby far exceeding the requirements of thestandard.

Amounts of surface ionic contamination of UHP PFA by anions such asbromide, chloride, nitrate, nitrite, phosphate and sulfate are eachbelow the respective reporting limit, which are all much less than theSEMI F57 limits for surface extractable ionic contaminants. Onlyfluoride levels in UHP PFA exceed the reporting limit, but still remainvery low, at 1% of the SEMI F57 limit.

Extractable levels of metallic contamination (e.g., resulting fromentrapped metal-containing polymerization catalysts used for thefluoropolymer resin manufacture, or erosion of metallic extrudercomponents) from UHP PFA are also extremely low, not only by pure waterextraction, but also by the much more aggressive extraction tests with35% hydrochloric acid solution, which is commonly encountered in thesemiconductor fabrication industry. All common metallic elements, exceptnickel, were detected at levels below the reporting limits, which aremuch below the SEMI F57 limits. Nickel concentrations were detectedwithin an acceptable limit as specified in the SEMI F57 standard.

The body 110 of the column packing 100 may be manufactured through ahot-melt extrusion manufacturing process (also referred to as an“extrusion” process). According to the present invention, the polymericmaterial may be processed in an extruder at an elevated temperature andextruded through a die-head. Non-limiting examples of elevatedtemperature for extrusion may range from about 190° C. to about 290° C.—including all temperature and sub-ranges there-between. In anon-limiting example, PFA may be extruded at an elevated temperature ofabout 260° C. In a non-limiting example, FEP may be extruded at anelevated temperature of about 200° C.

The die-head may comprise an opening that forms the correspondingcross-sectional geometry of the body 110. Upon extrusion, the acontinuous strand of the column packing 10 may be formed, whereby thestrand can then be cut to any desired length on the extrusion line.Alternatively, the strand may be coiled and stored, to be cut to anyfuture length as needed.

The extrusion process can produce a continuous tube or strand ofextrudate having a simple round, tubular cross-sectional shape (orprofile) to progressively more complex profiles incorporating multipleelements, internal passages (or lumens) and shapes contained within asingle outer shape. The outer shape of the extrudate is usually circularin cross section, but can also be square, rectangular or triangular, aswell as more complex polygonal outer shapes such as a hexagon. Accordingto the present invention, having the body 110 of the column packing 100formed of polymeric material and being able to manufacture via extrusionprovides the ability to generate the complex multi-channel shapes andprofiles that are not as readily accomplished with other materials suchas glass or metals.

In other embodiments, the column packing 100 may be fabricated usingother processes, such as the injection of low pressure air into theinterior of the molten extrudate, or vacuum sizing the molten extrudateas it enters into the cooling water tank, can be used to impartadditional precision and control to shape the finished profile.

Referring now to FIGS. 7 and 8, the present invention includes adistillation apparatus 1 comprising at least one column packing 100. Thedistillation apparatus 1 may comprise a plurality of the column packings100 supported by one or more supports 20. The supports 20 may be porousas to allow for vapor and/or gas to readily pass through. Duringdistillation, a composition may be passed through the distillationchamber 10, thereby

that are located inside of the distillation chamber 10. The supports 20may be a perforated layer. The distillation apparatus 1 may furthercomprise one or more of the column packings 100—preferably a pluralityof the column packings 100. For the distillation apparatus 1 comprisinga multiple supports 20, a plurality of the column packings 100 may belocated on the multiple supports 20 inside of the distillation chamber10.

The inlet 11 of the distillation chamber 10 may be fluidly coupled to afirst reservoir and the outlet 12 of the distillation chamber 10 may befluidly coupled to a second reservoir. The first reservoir may contain acomposition that is delivered to the distillation chamber 10 via theinlet 11, whereby the composition is subjected to distillation—asdiscussed in further detail herein. After distillation, the distilledcomposition may exit the distillation chamber 10 and be delivered to thesecond reservoir via the outlet 12.

Referring now to FIGS. 9 and 10, a column packing 1100 is illustrated inaccordance with another embodiment of the present invention. The columnpacking 1100 is similar to the column packing 100 except as describedherein below. The description of the column packing 100 above generallyapplies to the column packing 1100 described below except with regard tothe differences specifically noted below. A similar numbering schemewill be used for the column packing 1100 as with the column packing 100except that the 1000-series of numbers will be used.

The column packing 1100 comprises a body 1110 having a central channel1400 and a plurality of perimeter channels 1500 that include a firstperimeter channel 1500 a, a second perimeter channel 1500 b, a thirdperimeter channel 1500 c, and a fourth perimeter channel 1500 d. Thefour perimeter channels 1500 a, 1500 b, 1500 c, 1500 d, may be arrangedconcentrically about the central axis A-A and all have the samecross-sectional shape.

Each of the perimeter channels 1500 a, 1500 b, 1500 c, 1500 d, maycomprise an inner boundary formed by a portion of the outer surface 1301of the inner wall 1300, an outer boundary formed by a portion of theinner surface 1202 of the outer wall 1200, and a side boundary formed bya first major surface 1601 of a first rib element 1600 and a secondmajor surface of a second rib element 1600. The portion of the outersurface 1301 of the inner wall 1300, the portion of the inner surface1202 of the outer wall 1200, the first major surface 1601 of the firstrib element 1600, and the second major surface of the second rib element1600 may intersect each other to collectively form a closed perimeterdefining the respective perimeter channels 1500 a, 1500 b, 1500 c, 1500d.

According to this embodiment, each of the first, second, third, andfourth portions of the outer surfaces 1301 a, 1301 b, 1301 c, 1301 d ofthe inner wall 1300 may be curved—specifically, have a uniform radius ofcurvature as measured from the central axis A-A. Therefore, therespective inner boundaries of the first, second, third, and fourthrespective perimeter channels 1500 a, 1500 b, 1500 c, 1500 d may becurved and have a uniform radius of curvature as measured from thecentral axis A-A. According to this embodiment, each of the first,second, third, and fourth portions of the inner surfaces 1202 a, 1202 b,1202 c, 1202 d of the outer wall 1200 may be curved—specifically, have auniform radius of curvature as measured from the central axis A-A.Therefore, the respective outer boundaries of the first, second, third,and fourth respective perimeter channels 1500 a, 1500 b, 1500 c, 1500 dmay be curved and have a uniform radius of curvature as measured fromthe central axis A-A.

Referring now to FIGS. 11 and 122, a column packing 2100 is illustratedin accordance with another embodiment of the present invention. Thecolumn packing 2100 is similar to the column packing 100 except asdescribed herein below. The description of the column packing 100 abovegenerally applies to the column packing 2100 described below except withregard to the differences specifically noted below. A similar numberingscheme will be used for the column packing 2100 as with the columnpacking 100 except that the 1000-series of numbers will be used.

Each of the perimeter channels 500 a, 500 b, 500 c, 500 d, may comprisean inner boundary formed by a portion of the outer surface 301 of theinner wall 300, an outer boundary formed by a portion of the innersurface 202 of the outer wall 200, and a side boundary formed by a firstmajor surface 601 of a first rib element 600 and a second major surfaceof a second rib element 600. The portion of the outer surface 301 of theinner wall 300, the portion of the inner surface 202 of the outer wall200, the first major surface 601 of the first rib element 600, and thesecond major surface of the second rib element 600 may intersect eachother to collectively form a closed perimeter defining the respectiveperimeter channels 500 a, 500 b, 500 c, 500 d.

Specifically, a first perimeter channel 500 a may comprise an innerboundary formed by a first portion of the outer surface 301 a of theinner wall 300 that intersects a first side boundary formed by a secondmajor surface 602 of a first rib element 600 a, which intersects anouter boundary formed by a first portion of the inner surface 202 a ofthe outer wall 200, which intersects a second side boundary formed by afirst major surface 601 of a second rib element 600 b, which intersectsthe inner boundary formed by the first portion of the outer surface 301a of the inner wall 300—thereby collectively forming a closed perimeterthat defines the first perimeter channel 500 a.

A second perimeter channel 500 b may comprise an inner boundary formedby a second portion of the outer surface 301 b of the inner wall 300that intersects a first side boundary formed by a second major surface602 of the second rib element 600 b, which intersects an outer boundaryformed by a second portion of the inner surface 202 b of the outer wall200, which intersects a second side boundary formed by a first majorsurface 601 of a third rib element 600 c, which intersects the innerboundary formed by the second portion of the outer surface 301 b of theinner wall 300—thereby collectively forming a closed perimeter thatdefines the second perimeter channel 500 b.

A third perimeter channel 500 c may comprise an inner boundary formed bya third portion of the outer surface 301 c of the inner wall 300 thatintersects a first side boundary formed by a second major surface 602 ofthe third rib element 600 c, which intersects an outer boundary formedby a third portion of the inner surface 202 c of the outer wall 200,which intersects a second side boundary formed by a first major surface601 of a fourth rib element 600 d, which intersects the inner boundaryformed by the third portion of the outer surface 301 c of the inner wall300—thereby collectively forming a closed perimeter that defines thethird perimeter channel 500 c.

A fourth perimeter channel 500 d may comprise an inner boundary formedby a fourth portion of the outer surface 301 d of the inner wall 300that intersects a first side boundary formed by a second major surface602 of the fourth rib element 600 d, which intersects an outer boundaryformed by a fourth portion of the inner surface 202 d of the outer wall200, which intersects a second side boundary formed by a first majorsurface 601 of a first rib element 600 a, which intersects the innerboundary formed by the fourth portion of the outer surface 301 d of theinner wall 300—thereby collectively forming a closed perimeter thatdefines the fourth perimeter channel 500 d.

According to this embodiment, each of the first, second, third, andfourth portions of the outer surfaces 301 a, 301 b, 301 c, 301 d of theinner wall 300 may be planar. Therefore, the respective inner boundariesof the first, second, third, and fourth respective perimeter channels500 a, 500 b, 500 c, 500 d may be flat (i.e., planar). According to thisembodiment, each of the first, second, third, and fourth portions of theinner surfaces 202 a, 202 b, 202 c, 202 d of the outer wall 200 may becurved—specifically, have a uniform radius of curvature as measured fromthe central axis A-A. Therefore, the respective outer boundaries of thefirst, second, third, and fourth respective perimeter channels 500 a,500 b, 500 c, 500 d may be curved and have a uniform radius of curvatureas measured from the central axis A-A. According to this embodiment,each of first and second major surfaces 601, 602, of the first, second,third, and fourth rib elements 600 a, 600 b, 600 c, 600 d may beplanar—i.e., flat. Therefore, the respective first and second sideboundaries of the first, second, third, and fourth respective perimeterchannels 500 a, 500 b, 500 c, 500 d may be planar—i.e., flat.

While the invention has been described with respect to specific examplesincluding presently preferred modes of carrying out the invention, thoseskilled in the art will appreciate that there are numerous variationsand permutations of the above described systems and techniques. It is tobe understood that other embodiments may be utilized and structural andfunctional modifications may be made without departing from the scope ofthe present invention. Thus, the spirit and scope of the inventionshould be construed broadly as set forth in the appended claims.

EXAMPLES

Table 1 lists some commercially available column packings made from avariety of classic materials that exhibit excellent chemical resistance,stability and purity, but suffer from reduced surface area due to thelimited capability of the available manufacturing methods compared topolymer extrusion.

TABLE 1 Surface Area per Piece, mm² (similar sizes occupy same overallvolume per Packing Type piece) 5 mm diameter glass beads 79 (spheres) 8mm diameter glass beads 201 (spheres) Raschig Rings, glass, 5 mm OD × 5mm long 141 (simple cylinders with 0.5 mm wall thickness) Raschig Rings,glass, 8 mm OD × 8 mm long 377 (simple cylinders with 0.5 mm wallthickness) Thin sheet metal plates, 316 stainless steel, 50 5 mm × 5 mmsquare pieces formed into curved shape Thin sheet metal plates, 316stainless steel, 128 8 mm × 8 mm square pieces formed into curved shapeMCD-5, FEP or PFA fluoropolymer 592 5 mm OD × 5 mm long MCD-8, FEP orPFA fluoropolymer 309 8 mm OD × 8 mm long

Table 2 lists some of the MCD column packing sizes with respective datafor each.

TABLE 2 Approx. Approx. Common Approximate Number of Surface Unit ofVolume per Pieces per Area per Item No. Comparison 250 g 250 g 250 gMCD-5 250 g 500 cm³ 2200 6800 cm² MCD-8 250 g 600 cm³ 1140 6750 cm²MCD-10 250 g 1100 cm³ 1000 10,600 cm²

In addition to extreme chemical resistance, fluoropolymers alsowithstand much higher continuous use service temperatures than the muchmore inexpensive and commonly used thermoplastic polymers notedpreviously. Table 3 summarizes the continuous use temperatures of thedifferent polymers mentioned above.

TABLE 3 PFA all Polymer FEP grades PVDF ETFE LDPE HDPE PP PVC MaximumContinuous 200° C. 260° C. 129° C. 150° C. 79° C. 102° C. 121° C. 177°C. Use Temperature 392° F. 500° F. 265° F. 302° F. 175° F. 215° F. 250°F. 350° F.

What is claimed:
 1. A column packing for a distillation apparatus, thecolumn packing comprising: a first open end opposite a second open end:a central channel; a plurality of perimeter channels; and a bodyextending along a central axis between an upper end opposite a lowerend, the body formed of polymeric material and comprising: an outer wallan inner wall; and a plurality of rib elements connecting the inner wallto the outer wall; wherein the polymeric material is ultra-high purityperfluoroalkoxy alkane polymer containing up to 0.2% of the limitspecified in SEMI F57 for surface extractable Total Organic Carbon. 2.The column packing according to claim 1, wherein the central channel isconcentric with the central axis.
 3. The column packing according toclaim 1, wherein the plurality of rib elements are arrangedconcentrically about the central axis.
 4. The column packing accordingto claim 1, wherein the outer wall extends continuously between thefirst and second open ends of the body.
 5. The column packing accordingto claim 1, wherein the inner wall extends continuously between thefirst and second open ends of the body.
 6. The column packing accordingto claim 1, wherein the central channel has a circular cross-sectionalshape taken in a direction normal to the central axis.
 7. The columnpacking according to claim 1, wherein the central channel has apolygonal cross-sectional shape taken in a direction normal to thecentral axis.
 8. The column packing according to claim 1, wherein thecentral axis intersects both the first and second open ends, the centralchannel extending parallel to the central axis and the central channelcircumscribed by the inner wall.
 9. The column packing according toclaim 8, wherein the plurality of perimeter channels extend parallel tothe central axis, each of the plurality of perimeter channels defined byat least a portion of the inner wall, at least a portion of the outerwall, and at least two the plurality of rib elements.
 10. The columnpacking according to claim 9, wherein the outer wall is cylindrical andcomprises an outer surface opposite an inner surface; the inner wallcomprises an outer surface opposite an inner surface; and each of theplurality of rib elements comprise a first major surface opposite asecond major surface.
 11. The column packing according to claim 10,wherein each of the perimeter channels are formed by a portion of theinner surface of the outer wall; the outer surface of the inner wall,the first major surface of a first rib element, and the second majorsurface of a second rib element.
 12. A column packing for a distillationapparatus, the column packing having an upper end opposite a lower end,the column packing comprising: a body extending along a central axis,the body comprising: a central channel extending parallel to the centralaxis, the central channel comprising a first open end opposite a secondopen end; and a plurality of perimeter channels circumscribing thecentral channel, each of the perimeter channels comprising a first openend opposite a second open end wherein the multi-channel body is formedof ultra-high purity perfluoroalkoxy alkane polymer.
 13. The columnpacking according to claim 12, wherein first open end of the centralchannel and the first open end of each of the perimeter channels overlapwith the upper end of the column packing.
 14. The column packingaccording to claim 12, wherein second open end of the central channeland the second open end of each of the perimeter channels overlap withthe lower end of the column packing.
 15. The column packing according toclaim 12, wherein the body has a height as measured between first andsecond open ends of the central channel and plurality of perimeterchannels, and the body has a diameter as measured from an outermostsurface of the body, wherein the ratio of the diameter to the height ofthe body ranges from about 0.33:1 to about 3:1.
 16. The column packingaccording to claim 12, wherein the ultra-high purity perfluoroalkoxyalkane polymer contains up to 0.2% of the limit specified in SEMI F57for surface extractable Total Organic Carbon.
 17. A method of forming acolumn packing for a distillation apparatus, the method comprising: a)extruding a polymeric composition through a die to form a tube having acentral channel circumscribed by a plurality of perimeter channels; b)cutting the tube in a direction perpendicular to the central axis toform a body comprising the central channel and the plurality ofperimeter channels; wherein the polymeric composition is ultra-highpurity perfluoroalkoxy alkane polymer containing up to 0.2% of the limitspecified in SEMI F57 for surface extractable Total Organic Carbon. 18.The method of according to claim 17, wherein the composition in step a)is extruded at a temperature ranging from about 190° C. to about 290° C.19. The method according to claim 17, wherein subsequent to step b), aplurality of the bodies are collected and stored together.
 20. Themethod according to claim 17, wherein the tube has a diameter and thebody is cut to a length such that a ratio of the diameter of the tube tothe length of the body ranges from about 0.33:1 to about 3:1.